Protective helmets, particularly welding helmets, tend to be heavy and cumbersome. The weight of a protective helmet can be burdensome on a wearer who may often already be working in extreme conditions of heat and other adverse elements. The weight of the protective helmet adds further to that burden.
A head suspension system for a protective helmet must be adjusted to the particular requirements of the wearer for the helmet to be comfortable. An ill fitting helmet, especially one that is heavy, may be extremely uncomfortable for a wearer, which could lead to operating mistakes and, possibly, injury.
Adjustment mechanisms on conventional protective helmets, such as welding helmets, are typically either bulky, difficult to adjust, or both. Adjustment mechanisms that require a bulky adjustment knob can add a considerable weight to the protective helmet. Common adjustment mechanisms may also involve removable and replaceable bolts or set screws that can be very difficult to adjust. Bolts that must be undone often lead to a multiplicity of loose bolts, nuts and washers that may be difficult to reassemble. This can be especially true when the wearer is wearing protective hand gear such as gloves.
Some head suspension systems may be adjusted by repositioning straps. One example of a head suspension adjustment mechanism adjusted by repositioning a headband strap is disclosed in U.S. Pat. No. 5,608,917, Landis et al, Ergonomic Head Band Apparatus. An ergonomic head band includes a strap having first and second upwardly curved side arcuate segments, a front arcuate region and tails which couple together at the back of a wearer's head. The tails are repositionable on each other providing a common sizing adjustment. Face shields or other apparatus may be coupled to the head band.
Other headgear supports provide adjustability with headbands with ends that slide relatively to each other. Examples are found in U.S. Pat. No. 3,500,474, Austin, Adjustable Headband; U.S. Pat. No. 4,888,831, Oleson, Adjustable Head Band Suspension System For Use With Hard Hat Shell, providing a slidably disposed adjusting device; U.S. Pat. No. 5,896,586, Freund, Adjustable Headband Having a Resiliently Bowable Fastener Surface, having a plurality of longitudinally spaced slots and a resilient fastener with a channel to slidably receive the end with the spaced slots; and U.S. Pat. No. 6,341,382, Ryvin et al, One-Piece Adjustable Headgear Support, having an integrally formed slidable adjustment mechanism. However, such adjustment mechanisms are not always easy for a wearer in the field to adjust and may add unnecessary weight to the protective helmet.
U.S. Pat. No. 5,077,836, Idoff et al, Headgear, discloses a headgear for mounting protective equipment such as a visor. The head band includes a brow band section, side band section and a neck band section. The neck band portion includes an adjustment mechanism including slidable portions secured with a knob. In addition, the brow section includes an adjustable buckle. Again, the adjustment mechanism can be unduly difficult for a user to adjust and may add unnecessary weight to the headgear.
U.S. Pat. No. 4,942,628, Freund, Helmet Suspension Having Ratchet Adjustment, discloses a head protection or helmet suspension having a ratchet adjustment for the adjustment of the head suspension in size. An adjustment knob engages pins in the ratchet case to lock the head suspension size in position. The adjustment knob and ratcheting mechanism may add unnecessary weight to the helmet.
U.S. Pat. No. 5,571,217, Del Bon et al, Protective Assembly For The Protection Of The Human Head, discloses a protective assembly which has a circular support structure adapted to be connected to the head of the person wearing the protective assembly. A protective visor is pivotally connected to the support structure to be swiveled for a lower operating position and to an upper resting position. A rear ratcheting adjustment mechanism provides size adjustment for the headband. The ratcheting mechanism may add unnecessary weight to the helmet.
U.S. Pat. No. 7,007,306, Howard et al, Face Shield Assembly, discloses a face shield assembly including a frame and a removable protective element supported by the frame. The frame is pivotally supported on a support structure such that the frame can be moved between an upper (out of use) and a lower (in use) position. A rear adjustment knob allows a rear head band portion to be selectively secured in a slidable position providing rear size adjustment. Again, the rear adjustment knob and slide mechanism may add unnecessary weight to the helmet.